Bypass with 39 bridges

Project information

Construction project

Bypass with 39 bridges, viaducts and noise barriers

Customer

Provincie Limburg

Construction

Combination of BPL concrete and BPL paths

Location

Buitenring Parkstad Limburg , NL

Planing

HUESKER and a local engineer

Construction time

January 2014 – July 2019

Products used

Fortrac Systems

Project details

Steep wall stabilised by Fortrac Systems

Geogrid-reinforced noise barriers along the motorway

Situation

Parkstadt Limburg comprises 8 municipalities. The road infrastructure in this region was very chaotic and poorly connected. The new road was built as a regional bypass around Parkstad Limburg. This enables shorter journey times and reduces traffic volumes on side roads and residential streets. This leads to a significant reduction in traffic in the neighbouring villages and thus contributes to improved environmental protection. Access to the eastern side of Parkstad Limburg is now easier and safer. The 39 bridges, viaducts and noise barriers have been constructed along the 26 km route. The bridge abutments were mainly founded on piles or on a natural foundation, with a geogrid-reinforced sub-base or wall.

Solution

The loamy nature of the local soils meant that the ground was highly unstable in an undrained state, which is why parts of the load-bearing soil layer were replaced with sand to accommodate critical structures. In addition, a non-standard soil type called ‘Stol’ (a type of mixed aggregate) was used. The results of the batch tests were examined for their applicability in the actual earthworks; immobilisation (cement-bound contaminated soil) was also used, which, due to the high pH>9 content, led to the decision to use MPT grids. The viaducts were founded on piles, which were driven through the existing soil structure using pre-drilled holes. To construct an overhanging noise barrier, a complex structure was built on a 5 m high reinforced soil wall with a 10:1 slope. Due to the lack of space within the road profile, slope nailing was chosen to keep the slope stable during excavation. The minimum anchor length and the anchor forces to be absorbed were determined on the basis of internal stability. The anchor grid was defined based on the slope height and the geogrid width. These assumptions were passed on to the supplier of the claw anchors so that they could be translated into effective anchor lengths in combination with the standard soil parameters.

Advantages